<!-- 综合案例 -->
<script setup lang="ts">
import { computed, ref, watch } from 'vue'

// 定义水果对象的类型
interface Fruit {
  id: number
  icon: string
  isChecked: boolean
  num: number
  price: number
}
//定义存储键名
const KEY = 'fruitList'
// 水果列表
const fruitList = ref<Fruit[]>([
  {
    id: 1,
    icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/ll.png',
    isChecked: true,
    num: 2,
    price: 6,
  },
  {
    id: 2,
    icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/smt.png',
    isChecked: false,
    num: 7,
    price: 20,
  },
  {
    id: 3,
    icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/tg.png',
    isChecked: false,
    num: 3,
    price: 40,
  },
  {
    id: 4,
    icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/xg.png',
    isChecked: false,
    num: 10,
    price: 3,
  },
  {
    id: 5,
    icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/yl.png',
    isChecked: false,
    num: 20,
    price: 34,
  },
])

//持久化存储数据
watch(
  fruitList,
  () => {
    //数组列表数据改变时，将数据保存到本地存储中
    localStorage.setItem(KEY, JSON.stringify(fruitList.value))
  },
  { deep: true },
)
//获取本地存储数据
const res = localStorage.getItem(KEY)
//判断数据类型
if (typeof res == 'string') {
  fruitList.value = JSON.parse(res)
} else {
  //如果为空,给定默认数据
  fruitList.value = [
    {
      id: 1,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/ll.png',
      isChecked: true,
      num: 2,
      price: 6,
    },
    {
      id: 2,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/smt.png',
      isChecked: false,
      num: 7,
      price: 20,
    },
    {
      id: 3,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/tg.png',
      isChecked: false,
      num: 3,
      price: 40,
    },
    {
      id: 4,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/xg.png',
      isChecked: false,
      num: 10,
      price: 3,
    },
    {
      id: 5,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/yl.png',
      isChecked: false,
      num: 20,
      price: 34,
    },
  ]
}

//点击空占位图,使其显示默认数据
const resetData=()=>{
  fruitList.value = [
    {
      id: 1,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/ll.png',
      isChecked: true,
      num: 2,
      price: 6,
    },
    {
      id: 2,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/smt.png',
      isChecked: false,
      num: 7,
      price: 20,
    },
    {
      id: 3,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/tg.png',
      isChecked: false,
      num: 3,
      price: 40,
    },
    {
      id: 4,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/xg.png',
      isChecked: false,
      num: 10,
      price: 3,
    },
    {
      id: 5,
      icon: 'https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/yl.png',
      isChecked: false,
      num: 20,
      price: 34,
    },
  ]
}

// 删除商品
const deleteGoods = (id: number) => {
  fruitList.value = fruitList.value.filter((item) => item.id !== id)
}

//修改个数,加
const addNum = (id: number) => {
  //  根据id找到元素,累加
  // 使用find检索元素,找到了就是唯一的一个,找不到就返回undefined
  const res = fruitList.value.find((item) => item.id == id)
  res!.num++
  console.log(res)
}
//修改个数,减
const reduceNum = (id: number) => {
  //  根据id找到元素,递减
  const res = fruitList.value.find((item) => item.id == id)
  if (res!.num <= 1) return
  res!.num--
}

//是否全选
const isCheckAll = computed({
  get() {
    return fruitList.value.every((item) => item.isChecked)
  },
  //赋值,点击全选时回传给checkbox进行赋值
  set(value) {
    // 遍历 fruitList,将所有isChecked属性改为value
    fruitList.value.forEach((item) => (item.isChecked = value))
    //  console.log(value);
  },
})

//总价
const totalPrice = computed(() => {
  const total = fruitList.value.reduce((sum, item) => {
    if (item.isChecked) {
      return sum + item.num * item.price
    } else {
      return sum
    }
  }, 0)
  return total
})
//选中的总个数
const totalNum = computed(() => {
  //将勾选的商品和个数进行求和
  const num = fruitList.value.reduce((sum, item) => {
    if (item.isChecked) {
      return sum + item.num
    } else {
      return sum
    }
  }, 0)
  return num
})
</script>

<template>
  <div class="app-container" id="app">
    <!-- 顶部banner -->
    <div class="banner-box">
      <img src="https://hongm-1312445828.cos.ap-nanjing.myqcloud.com/sg_top.png" alt="" />
    </div>
    <!-- 面包屑 -->
    <div class="breadcrumb">
      <span>🏠</span>
      /
      <span>购物车</span>
    </div>
    <!-- 购物车主体 -->
    <div v-if="fruitList.length > 0" class="main">
      <div class="table">
        <!-- 头部 -->
        <div class="thead">
          <div class="tr">
            <div class="th">选中</div>
            <div class="th th-pic">图片</div>
            <div class="th">单价</div>
            <div class="th num-th">个数</div>
            <div class="th">小计</div>
            <div class="th">操作</div>
          </div>
        </div>
        <!-- 身体 -->
        <div class="tbody" v-for="item in fruitList" :key="item.id">
          <div class="tr active">
            <div class="td"><input type="checkbox" checked v-model="item.isChecked" /></div>
            <div class="td">
              <img :src="item.icon" alt="" />
            </div>
            <div class="td">{{ item.price }}</div>
            <div class="td">
              <div class="my-input-number">
                <button class="decrease" @click="reduceNum(item.id)">-</button>
                <span class="my-input__inner">{{ item.num }}</span>
                <button class="increase" @click="addNum(item.id)">+</button>
              </div>
            </div>
            <div class="td">{{ item.num * item.price }}</div>
            <div class="td"><button @click="deleteGoods(item.id)">删除</button></div>
          </div>
        </div>
      </div>
      <!-- 底部 -->
      <div class="bottom">
        <!-- 全选 -->
        <label class="check-all">
          <input type="checkbox" v-model="isCheckAll" />
          全选
        </label>
        <div class="right-box">
          <!-- 所有商品总价 -->
          <span class="price-box"
            >总价&nbsp;&nbsp;:&nbsp;&nbsp;¥&nbsp;<span class="price">{{ totalPrice }}</span></span
          >
          <!-- 结算按钮 -->
          <button class="pay">结算( {{ totalNum }} )</button>
        </div>
      </div>
    </div>
    <!-- 空车 -->
    <div @click="resetData" v-else class="empty">🛒空空如也</div>
  </div>
</template>

<style scoped>
@import './style/inputnumber.css';
@import './style/index.css';
</style>
